THE PATH OF EVOLUTION 



motion is the transference of heat, light and electric- 

 ity. It is not ponderable matter. 



7th. All substances are composed of atoms com- 

 bined into molecular masses. These molecules are 

 in constant motion, their condition varying from that 

 of a solid, in which they have only vibratory motion, 

 to that of a liquid, in which they have vibratory and 

 also limited translatory motion, and to that of a gas in 

 which they have ' vibratory motion as a consistent 

 molar substance, or mass, and also unlimited molec- 

 ular, translatory motion. These three conditions are 

 dependent upon that state of inter-atomic motion 

 called heat. It is supposed to be absent entirely 

 from all matter at the temperature of the absolute 

 zero ( 460 degrees F.). By which absence of heat 

 all bodies previously gases or liquids would become 

 solids, and all vibratory motion in matter, such as 

 heat, would cease. With the increase of the atomic 

 motion of heat, the several stages of fusion or 

 liquidity, and of vaporization, or the gaseous state, 

 appear. A definite amount of heat motion dis- 

 appearing as heat in each change of state, being 

 transformed into the increased molecular motion of 

 the liquid or of the gas (with water 144 degrees F., 

 in the melting of ice ; 965 degrees F. in water when 

 boiling). The molecules of a gas move constantly in 

 right lines in all directions until they meet in colli- 



208 



